The really addictive and dangerous drugs are the ones that society would most benefit from decriminalization. Sure, it's not great when college kids get a criminal record from smoking reefer, but that's the least of our drug problems in the US. It's the dangerous drugs that are killing people and orphaning children, and those are the people who have the most trouble getting effective help due to the criminal nature of their addiction.

Portugal had a bad heroin problem in the 90s. How did they fix it? They decriminalized possession of every drug, including heroin. Instead of sending users to jail, they now send them to treatment. It was an overwhelming success.